Sulphurized teepene oil and process



Patented Sept. 12, 1933 UNITED STATES SULP-HURIZED TERPENE OIL AND PROCESS OF PREPARING'THE SAME Robert 0. Palmer and Paul 0. Powers, Pensacola, Fla., assignors to Newport Industries, Inc., Pensacola, Fla"; a corporation of Delaware No Drawing. Application May 31, 1932 Serial No. 614,620 r 21 Claims.

This invention relates to a novel sulphur-terpene oil composition and to a process of making the same. More specifically, this invention relates to the preparation, of a sulphurized.

pine oil composition useful, for example, as a cutting oil base and as a flotation oil base in mineral separations When sulphur is chemically combined with "terpene oils, such as nine oil, terpineol and the like, either singly or in admixture, one of the reaction products obtained is water. We have found that the amount of water given off is equal to the amount of water liberated whenthe tentiary terpene alcohols present in the oil being treated are dehydrated to form unsaturated terpene hydrocarbons. 'This has been proven by treating pure alpha terpincol, which is the principal tertiary terpene alcohol present in pine oil, with sulphur at'the refluxing temperature.

When the secondary terpene alcoholspresent in. terpene oils, such as pine oil and the like, are treated with sulphur no water is liberated and no sulphur is combined. Furthermore, if un=- saturated terpene hydrocarbons such as dipen tens, liincnene, terpinene and the like are treated with sulphur in the same manner, combination is readily effected.

The unsaturated terpene hydrocarbons referred to above are the type of hydrocarbons resulting from the dehydration of tertiary terpene alcohols. Furthermore, when pure terpineol is reacted with small amounts of sulphur (fcrexample 5%) so that the total sulphur combination is not the water given oil is equal to that obtained by the total destruction of the alcohol was; and when the oil formed which has not cd is distilled off from the sulphur combinaund to be a nearly pure unsaturated he hydrocarbon.

"cries have led us to believe that mation of reaction prodic materials will eihydroxyl group from 1 sulphur is caused such e oil, sees, the reaction prodi cutt cg oil base (U. S, No;

y. es we ha e discovered the nature reaction, namely, that the tertiary aloo- "'esent in the terpene oil are dehydrated to form unsaturated terpenehydrocarbons and the sulphur then combines with these hydrocarbons,

it would be a natural conclusion that, i! such hydrocarbons alone. are combined with sulphur, the. resulting reaction product would make anexccllent cutting oil base. This, however, is not the case, since such a product is not a cutting oil 6:) at all. Furthermore, pine oil itself is not a cut ting oil.

While there is no proyen theory that explains why materials make good cutting oils, it has been suggested that probably the most important property of cutting oils is adhesion. Some authorities have further suggested. that adhesion is dependent upon the presence of active groups, sometimes referred to as polar groupapin the molecules. Examples of suohpolar groups are hydroxyl groups, carbcxyl groups, double bonds and the like. The correctness of this suggestion may be shown by adding a secondary terpene alcohol to an unsaturated terpene hydrocarbon whose double bonds have been saturated with sulphur and which is itself a poor cutting oil By doing this the cutting properties of the composition are greatly improved.

These experiments have led us to the conclusion that if sulphur could be made to combine with terpene oils, such as pinepil, without destroying the hydroxyl groups of the tertiary alcohols pres-' ent, the product would have cutting properties I superior to terpene oilsdn which sulphur had been combined in such a manner as to destroy the hydroxyl groups of the tertiary alcohols.

We have now found that a combination of ter pene oils, such as pine oil, and sulphur can be effected, without dehydrating the tertiary alcohols, by refluxing the terpene' oil with sulphur in the presence of a small amount of any alkali, or base forming substance which will chemically combins with hydrogen sulphide to form basic compounds. The basic compound so formed acts to protect the tertiary alcohols from the dehydrating action that might otherwise result from the acidity of the reaction products present in the mass at any given time. i

We have found further that if the reaction is carried out in the presence of oxygen or an oxy- 109 gen containing gas and preferably also the presence of an oxidation catalyst a considerable saving in sulphur is efiected. the sulphurization process large amounts of sulphur are liberated as hydrogen sulphide. The oxidizing conditions and the presence of an oxidation catalyst causes the hydrogen sulphide to be oxidized to sulphur during the reaction.

-The simplest way to prevent the elimination of hydrogen sulphide is to pass air through the into sulphur. In general any catalyst which will 1 accelerate the oxidation of hydrogen sulphide is operative.

It is therefore an object of this invention to produce a novel sulphur-terpene oil composition by reacting a terpene oil with sulphur in the presence of an agent capable-oi reacting with sulphur to form a basic poly-sulphide.

It is a further object of this invention to prepare a novel sulphur-terpene oil composition in which the tertiary alcohol groups present in the terpene oil remain substantially intact.

It is another object of this invention to provide a process for preparing cutting oil and flotation oil bases by reacting terpene oils with sulphur in the presence of alkalies.

It is a specific object of this invention to prepare a novel sulphur-pine oil composition containing substantially all of the initially pres'ent tertiary alcohol groups in the pine oil by reacting the pine oil with the sulphur in the presence of an alkali.

It is another specific object of this invention to produce a novel sulphur-terpene oil compositionby reacting a terpene oil with sulphur in the presence-oi alkali while maintaining oxidizing conditions sufiicient to convert hydrogen sulphide to sulphur. I

Another object of this invention isto provide an economical process for the preparation of sulphur -terpene oil compositions by reacting terpene oils with sulphur in the presence of an oxidation catalyst -while maintaining oxidizing conditions .during the-reaction.

Other and further important objects of this invention will be apparent from the disclosures in the specification and theaccompanying claims.

Among the basic materials which we have found to be operative to preserve the alcoholic groups in our process are all the alkalies which form basic polysulphides with sulphur. Examples of such alkalies are sodium and potassium hydrox ide, sodium and potassium carbonate, calcium hydroxide,'triethanol amine, ammonium hydroxide and the like. Since ammonium hydroxide is relatively volatile, the protection afforded by it is continued only so long as the volatile ammonium sulphide produced by reaction remains in the refluxing mass.

Metallic oxides such as lead or zinc oxide, and organic bases such as aniline, pyridine and the like do not-prevent the dehydration of the terpene alcohols. This is no doubt due to the fact that these compounds immediately combine with sulphur to form permanently neutral compounds. Metallic oxides such as, for example, copper oxide are operative however as oxidation catalysts tc prevent elimination of hydrogen sulphide and thereby reduce the amount'oi sulphur required.

Without limiting our invention to any particular procedure, the following examples, in which parts by weight are given, will serve to illustrate our process in its preferred form.

Example I This example illustrates the process-of preventing destruction of the terpene oils without attempting to prevent elimination of H25.

100 parts of pine oil havinga specific gravity of about 0.933 to 0.935, 50 parts of sulphur and may be normally present in the pine oilinitially used. The alkali may or may not be added in water solution. If no water is used it is prefer-. able to have the alkali in a. finally powdered state. As little as i; part of sodium hydroxide in a 50% water solution gives the desired results.

After the sulphur is combinedso that it will no longer precipitate on cooling, the heating may or may not be continued at higher temperatures, say about 200 C., until liberation of hydrogen sulphide ceases. In the event that the continued heating procedure is carried out, the-amount of sulphur in the final product is about 20%. If the heating is not continued until evolution of hydrogen sulphide ceases, the amount of combined sulphur in the finished product is about 23%.

The reaction'product is given a single wash with an aqueous solution of caustic soda containing about 1% of caustic soda on the basis of the oil present. The washing is preferably carried out at about 100 C. to remove any corrosive sulphur compounds such as mercaptans and any occluded or dissolved hydrogen sulphide. The alkaline water is allowed to settle and de-' canted off. The oil may then be given successive washes with water at about 100 C. until the wash water is neutral to litmus paper or other indicator and gives no brown coloration with copper sulphate. The product is finally dehydrated to remove occluded or dissolved water. The dehydration is preferably carried out by heating the oil under reduced pressure at a temperature below 100 C.

The product is a non-corrosive material suitable for use as a cutting oil base and is free from objectionable odors. The product is also useful as a flotation agent in the separation of minerals from ore mixtures.

The amount of sulphur that may be held in permanent combination by this process will vary with the composition of the terpene oil used. The amount held in combination depends upon the proportion of unsaturated terpene hydroj carbons and tertiary terpene alcohols present in the terpene oil. For example, a standard grade steam distilled pine oil of specific gravity 0.933 to 0.935 containing from 10 to 15% hydrocarbons and about 60% tertiary alcohols will permanently combine with about 50% by weight of sulphur.

In order to obtain the maximum amount of sulphur in the final product by this-process, it is necessary to start with about 100 parts by weight of the pine oil and '75 parts by weight of sulphur. 1

When so'large an amount of sulphur is used, it is advisable to use a little' more alkali, for example, part by weight.

Example II part of sodium carbonate are heated at the restantially all oithe tertiary alcohol groups in a free state that were present in the terpene oil before sulphurization.

14. As a new composition, a sulphurized terpene oil product suitable for use as a cutting oil or flotation agent base which is substantially non-corrosive free from objectionable odors and contains substantially all of the free tertiary alcohol groups that were present in the terpene oil before sulphurization.

15. The process of forming a sulphurized oil composition, which comprises heating sulphur with a terpene oil at temperatures between 165 C. and 195 C. in the presence of an allgali which forms a basic polysulphide with sulphur.

16. The process of preparing a sulphurized pine oil composition, which comprises heating pine oil with sulphur at temperatures between 180 to 190 C. in the presence of an alkali which forms a basic sulphide with hydrogen sulphide.

17. As a new composition of matter, anoncorrosive, odorless, sulphurizedterpene oil coma position in which the tertiary alcohol aoups oi the terpene oil have not been destroyed.

18. As a new composition, a sulphurized terpene ofl product formed by heating sulphur with a terpene oil in the presence of a basic reacting material so as to prevent decomposition of the tertiary alcohol groups present in the terpene oil.

19. The process of preparing a sulphurized terpene oil composition which comprises heating- 100 parts of pine oil, 50 parts of sulphur, and

a small amount or sodium carbonate to temperatures of 180 to 190 C. until the sulphur is combined so that it will no longer precipitate on cooling.

' 20. The process of forming a sulphurized oil composition, which comprises heating sulphur with a terpene oil at the reflux temperature in the presence of an oxygen containing gas, an alkali which forms a basic sulphide with hydrogen sulphide and an oxidation catalyst.

21. The process of preparing a sulphurized pine oil composition which comprises heating together 100 partsof pine oil, 30 parts of sulphur, a small amount of an alkali metal carbonate and about 0.5 parts of copper hydroxide to temperatures between 165 C. to 195 C. over a period of from 1 to 3 hours while continuously blowing air through the mass. ROBERT C. PALMER.

PAUL O. POWERS. 

